Hi there, I've been talking about upgrading/ rebuilding my current pc for a few years now.. Well i've finaly started buying the parts for it, The only things i am using from my curreny computer is my Video Card, My DVD Burner and my Power Supply. My Card is a Sapphire ATI X1800XT, And my Power Supply is a Antec 550 Watt True Power 2.0, I've already bought my case, I bought a Antec 900, I'm very happy with it, It looks awesome.. And i just now bought the CPU, Just waiting for the UPS guy to drop it off.. My CPU is a AMD Phenom II X2 550 Black Edition Callisto 3.1GHz 2 x 512KB L2 Cache 6MB L3 Cache Socket AM3 80W Dual-Core Processor. I figured i don't need to upgrade my power supply, Because the AMD Athlon 3800+ is a 89 Watt CPU. That's what i currently have in my computer. I'm going to buy a new OS, Windows XP.. I no longer have the code to my current OS.. I upgraded my HP computer by getting a better power supply, Adding a real video card and changing out the case.. I didn't think to keep the case, Or Write down the number on the side of the case lol.. So I plan to buy a new Hard Drive aswell. I'm looking at a Western Digital Caviar Black WD6401AALS 640GB 7200 RPM 32MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive, It will take care of anything i'll ever want to put on it.. My Current hard drive is a 200GB one.. So that one is a very big upgrade.. I am kind of lost on the mother board, On a couple of different forums i read that the CPU i bought can be unlocked to use all 4 cores if i have a motherboard that's able to do that. Mainly i'm looking at two different mother board, They both have good and bad reviews.. First one is a ASUS M4A79XTD EVO AM3 AMD 790X ATX AMD Motherboard, And the second one is a GIGABYTE GA-MA790X-UD4P AM3/AM2+/AM2 AMD 790X ATX AMD Motherboard.. If you guys or gals have any suggestions that could point me in the right direction in picking a mother board, I would be very grateful! I'm looking to spend up to around $150 for a mother board btw. ^^

That Phenom II 550 you have could be a quad core with 2 of it's cores disabled or it could just be only a dual core in the first place. So it's still down to luck, there's a big chance that the processor you have doesn't have two other unlockable cores.

+1 on the asus, OP. I have had Asus boards for years, and they have been great, plus the ASUS M4A79XTD EVO is a nice system with plenty of ports, expandability and options.
I would, again, warn AGAINST windows XP. There is no reason to go that route with Windows 7 hitting in a month, and is SO much better. Not to mention 64-bit, since if you do gaming, you will want to aim for ~4+ gb ram.

Suggest the GiGabyte MOBO for you ,I have always used the GB MOBO,it have nice compatiable and stability ,I used 10 years.
From Celeron 533 to Athlon X2 BE,I use with least worry,so Phenom is not the problem,trust me.

Yeah. The posters above give good points. If your gaming a better video card is a must. Unless it currently suits the games you are playing. Or maybe not playing...It's also ok that you threw away the sticker along with your old case...It's stuck to the motherboard. You should also at least get windows vista...DX10 is so much better than DX9. As well as allowing for more performance improvements, but only if your computer is good enough. Which it is. Get at least 4 gB of ram.